Nathan w



(No Model.) N. W. CONDICT, Jr.

BALANCED SLIDE VALVE. No. 275,356. Patented'Apr.10,1883.

oc 5 a UNITED STATEs PATENT OFFICE.

BALANCED SLI DE-VALVE.

SPECIFICATION forming part of Letters Patent No. 275,:356, dated Aprl 10, 1883.

Application filed January 9, 1882. Renewed September 11, 1882. (No model.)

To all whom 't may concrn Be it known that I, NATHAN lV. CONDICT, Jr., a citizen of the United States, residing in Jersey City, New Jersey, have invented certain lnprovenents in Balanced Slide-Valves, of which the following is a specific-ation.

My invetion relates to a device for relieving` the slide-valves of steam-engines from undue pressure of stean; and my invention con- Ssts nainly in comhining a slide-Valve with certain balanced bars secured within the valvechest for the above purpose.

In the acconpanying drawings, Figura l is a trausverse section ot'a valve-chest with my improved balanced valve; Fig. 2, a longitudinal section ot' the valve-ehest and side view of the valve; Fig. 3, a perspective view of the valvc drawn to a reduced scale; and Fig. 4, a view of a modification, also drawn to a reduced scale.

lu Figs. 1 and 2, Arepresents the Valveface of asteam--ylinder; a a', the usual steamports, and b tlre eXhaust-port.

B is the slde-valve, which, with the exception ot' the wings d d, refet-red to hereinafter, may be sinilar to those of ordinary construction, the valve having iu the under side the usual recess, formiug an exhaust-passage, and in the top a recess for the valve-spindle, which is secured to the valve in any wellknown manner, and passes through a stufting-hox in the valve chest D.

Two balance bars or platcs, Gr G, hear each on two supports, H H, secured, in the present iustance, to the valve-face A. Each halance-bar is confined to the tops of the supports by a spring, J, on which, near the ends, hear nuts m m, adapted to bolts I, projecting` upward f'onthesupportsH. Bytu-ningthese nuts the bar may be forced down onto the supports with more or less pressure through the medium of the spring. A nice aljustment of the balance-bars will he required, so that while they are always in rigid contact with the supports they shall always hear lightly on the wings d d, and so that, while no undue frietiou is created by the sliding of the wings of the valve in contact with the balance-bars, the steam admitted to the chest cannot get between the bars and the wings of the valve.

The only portion of the top ot' the valve exposed to the pressure of ste-an is that between the bars Gr Gr, and this pressure is in part counteracted by that against the under side of the wings d d,- but the area ot' these wings should he so regulated that there shall be a slight excess ot' pressure on the top of the valve, so that it will always keep its seat. It is not essential that the balance-bars should he secnred to the valve-face A of." the steazncylinder.

ln Fig. 4 two vertically-ad ustahle anglehars are secured to the sides of the steanchest, and are arranged to cover so much of an ordinary slide-valve that the pressure of stean on the latterwill he g'eatlydininished.

The springs J for keeping the balance-bars down on their hearings are not essential; but I prefer then,because a yielding pre sure applied to the bar is, in my opinion, superior to a rigid pressure.

Instead of the rigid hearings H H for the balance-bars, these supports may consist of springs capahle ot' vielding to thepressure exerted by nanipnlating the nuts m when vertical alljustment is required, hnt too strong to yield to the pressure ot' stean, l'or it is essential to my invention that the bars should be suhstantially fixed within the srean-chest.

The balance-bars may, it' desired, he united or made iu one piece; but I prefer separate bars.

I claim as uy iuvention 1.. The conhination of a slide-valve with balance-bars secured within the valve-chest and adapted to the back of the valve, sul)- stantially in the manner described.

2. The conbiuatiou of a slide'valve having Wings d d, with balance-bars G G,secured within the valve-chest and adapted to the valve and its wings, substantially in the manner described.

In testimony whereof I have signed my name to this specification in the presence ot' two subscrihing witnesses.

N. W. CONDICT, JR.

Witnesses:

HARRY DRURY, HARRY SMITH. 

